Wednesday, April 16, 2014

Blender Limited Dissolve ~ A love Letter

I confess I feel a bit like I am revealing a dirty secret, but it's such a recent and delicious discovery for me that I wrote a love letter (illustrated of course) to a Blender operator and I'm going to show you my solution to a workflow problem that has bugged me all week.I've been sculpting and painting these cute little figures in ZBrush but then taking them back to Blender to get ready for SL. Now I don't know if you know this, but ZBrush tends to encourage some pretty high poly work, certainly way beyond what Second Life is prepared to allow.

He's cute, right, but he and his little friends have given me nothing but grief at the finishing up for Second Life stage. I tried exporting subdiv 1 from ZBrush, about 4-5k polys - reasonable for SL, but barely enough to wear their normal maps which are supposed to preserve details such as facial features. Then there were the textures to worry about. I polypainted them in ZBrush, which being ZBrush uses an equation something like 1 texture pixel per poly, so since a 1024 has more than a million pixels, you better have more than a million polys while you paint. But woe to anyone who thinks she can drop that same texture on a subdiv 1 and still expect to see any detail let alone pretty. Subdiv 2 wasn't much better, and now I was spending a significant chunk of time trying to reduce the face count before upload. If he was jewelery or a worn item, of course, SL being SL, I could get away with as much as the uploader would allow... cough. This would not be the responsible thing to do, but desperate times call for desperate measures.And I think I found the ideal desperate measure - Limited Dissolve in Blender. I am head over heels in love with it. First let's be clear - this is not exactly sound retopology practice. I'm not even sure some of what I ended up with deserves the name topology. The only way you might end up wanting to use this over say, removing edge loops or doing retopo was if you happened to have some very high poly models that already have polypainted textures and UV maps, meaning it's a bit late for retopo, and a bit dense to be bothering with removing edge loops, and too soon to decimate.Now I know what you're thinking, maybe that whole work flow is flawed, maybe I should give up polypainting textures in ZBrush and go back to texture in Blender or Photoshop after retopo but, but, but sob, I just can't.So if you can't keep from sculpting and polypainting but you still want to strip away enough geometry to make a viable SL trinket, here's my dirty secret love letter to Limited Dissolve.

Ok, if a one button reduction from 171 faces to 5 isn't enough to make you all tingly, I am truly surprised you read this far. If you are feeling pretty excited try to hang on a bit longer so you'll know some of what to expect on the honeymoon.

So far I have no way to predict which areas will work first try, or what sort of angle will produce the desired results. More careful study might answer those questions, but it all happens so fast and it's so easy to tweak, that the only dilemma is what you will say when someone points and laughs at your huge randomly placed ngons.whatever